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PEDIATRIC �UPPER AIRWAY EMERGENCIES �

Carolyn Rosenczweig, BA, MD, CCFP, FRCPCEmergency Physician

QUESTION:

WHAT WAS THAT

SOUND?

BY THE END OF THE HOUR YOU WILL HAVE A(N)

!  Understanding of the unique anatomic features of the pediatric airway.

!  Appreciation of the initial management of a child with impending airway obstruction.

!  Differential diagnosis for pediatric upper airway obstruction.

!  Organized approach to the child with an upper airway infection.

USING A CASE BASED APPROACH:

!  Review the anatomy of the pediatric airway

!  Definition!  Causes!  Critical Interventions!  Management

Let’s Get Started! QUESTION:

List as many points as you can on how the pediatric airway differs from the adult.

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Pediatric Vs. Adult Airway! Large head! Short neck! Small nares! Loose teeth! Small mandible! Long uvula! Long epiglottis! Friable mucosa! High larynx C3-4 (adult C4-5)! Small cricoid

Pediatric Vs. Adult Airway! Slanted chords! Pliable trachea! Immature alveolae! Pliable chest wall! Gastric dilation

The Respiratory Tract The Larynx•  Main function:

speech production & airway protection

•  Supraglottic: above the vocal chords

•  Glottic: at the vocal chords

•  Subglottic: below the vocal chords

Larynx & Respiratory Cycle

•  Chords close at end of the expiratory phase and rest.

•  Chords open at beginning of the inspiratory phase

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CASE 1

"  Previously healthy 3 year old with a one day history of fever, decreased PO intake, and increasingly restless behavior over the past 2 to 3 hours.

WHAT IS YOUR DIFFERENTIAL

DIAGNOSIS?

WHAT WOULD YOU DO RIGHT AWAY/NOT DO RIGHT AWAY? WOULD YOU…

R

R

R

CASE 2� A 2.5 year old girl with a

3 day history of worsening sore throat, bilateral ear ache, and fever x 16 hours. She is not moving her neck.

� She is lethargic and appears quite dry (as discerned from her poor skin turgor and lack of tears)

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WHAT IS YOUR DIFFERENTIAL

DIAGNOSIS?

WHAT WOULD YOU DO RIGHT AWAY/NOT DO RIGHT AWAY?

Supraglottic Airway Diseases Supraglottic Pathology  Supraglottic part of the

airway: Nose  Pharynx  Epiglottis  Surrounding structures

  Problems here = expiratory stridor + respiratory distress

DDx Supraglottic Diseases

# Congenital# Micrognathia# Pierre Robin# Treacher Collins# Down# Storage Diseases# Choanal Atresia# Lingual Thyroid# Thyroglossal Cyst

# Acquired# Adenopathy# Tonsillar Hypertrophy# Foreign Body# Pharyngeal Abscess# Epiglottitis

QUESTION: Epiglottitis

� Why has the incidence declined substantially over the past 15 years?

� What is the age range typically involved?� What are 3 other organisms which can cause this?� What is the classic radiological finding?� Which antibiotic(s) would you use?

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Epiglottitis  Incidence has declined due to the

widespread use of the Haemophilus influenzae B (HIB) vaccine.

  Epiglottitis usually affects children between 3 and 7 years old.

  Three other causal organisms:  Beta-hemolytic streptococcus  Staphylococcus aureus  Streptococcus pneumoniae

  Classic radiological finding is the “thumb print”.

EpiglottitisDefinition

An inflammation of the structures above the insertion site of the glottis.

Pathophysiology  Respiratory transmission  Bacteria penetrate the mucosal barrier, invade the blood

stream, and trigger an inflammatory cascade which leads to edema of the epiglottis and surrounding structures.

  Bacteremia can also lead to infection of the meninges, lungs, skin, joints, and ears.

History� Characteristic abrupt onset of severe symptoms -

often less than 24 hours� Fever usually is the first symptom, followed rapidly

by stridor and labored breathing � Fever > 40°C� Dysphagia, muffled voice, and sore throat are

common.� Cough and ear pain occur less frequently.

Physical Findings�  The child appears toxic.�  Shock may occur early in the course of the disease.� Marked restlessness, irritability, and extreme anxiety are

common.�  Child will sit in the tripod position, their mouth may be open

wide and tongue protruding.� An affected child often drools because swallowing is difficult

or painful.�  Stridor can occur with marked accessory muscle use.�  Tender anterior cervical lymphadenopathy

Management� ABC’s�  Racemic epinephrine administration plays little role in the

management of infectious or thermal epiglottitis and is not indicated.

� Appropriate antibiotics include:� ceftriaxone � cefotaxime� cefuroxime or a combination of � ampicillin and chloramphenicol� As in all invasive HIB infections, it is recommended that contacts

receive rifampin chemoprophylaxis.�  Corticosteroids have no proven efficacy for treating

epiglottitis.

QUESTION: �Retropharyngeal Abscess

� What is the “retropharyngeal space”?� What is the age range?� What organisms are typically responsible?� What are typical clinical features?� How do you make the diagnosis?� What is the management?

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Retropharyngeal Space

❚  The potential space is bordered by the posterior pharyngeal wall and the prevertebral fascia

❚  Extends from the base of the skull to level T2❚  Contains the lymph nodes that drain the nose, pharynx,

sinuses and ears

Retropharyngeal Abscess

Age Range❚  The age range is wide with most cases occurring

between 6 months to 6 years and the mean being 3 to 4 years.

Organisms❚  Staphylococcus aureus❚  Group A streptococcus❚  Anaerobes (Bacteroides)

Retropharyngeal AbscessClinical Features❚  Fever❚  Sore throat❚  Meningismus❚  Torticollis❚  Trismus❚  Neck swelling❚  Unilateral or bilateral cervical lymphadenopathy❚  Drooling❚  Stridor❚  Muffled voice - “hot potato” voice❚  Prefer to line supine with head extended

DiagnosisMaking the Diagnosis❚  A careful examination might

reveal a bulging posterior pharyngeal wall

❚  Lab tests often inconclusive❚  Lateral soft tissue of the neck

taking during inspiration, with the neck extended

❚  A retropharyngeal space that is more than twice the diameter of the vertebral body

❚  Sometimes an air-fluid level is seen, especially in perforation and anaerobic infections

❚  CT Scan - modality of choice

Retropharyngeal Abscess� ABC’s

� Appropriate antibiotics include:� Clindamycin is the first line of treatment� Clindamycin can be used alone or in combination with cefoxitin or a beta-lactamase–resistant penicillin, such as ticarcillin/clavulanate, piperacillin/tazobactam, or ampicillin/sulbactam

�  Consult ENT

And now for something completely different!

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Diseases of the Larynx

◗  Congenital◗  Laryngomalacia◗  Laryngeal Web◗  Vocal Cord Paralysis

◗  Acquired◗  Laryngeal Papillomas◗  Foreign Body

Laryngomalacia

❚  Is the most common cause of chronic stridor in infants and young children.

❚  Results from flaccidity of laryngeal structures and tissues causing them to collapse into the airway.

❚  Note the collapsed in epiglottis and pulled in arytenoid mucosa during inspiration.

❚  Symptoms usually worsen with supine position and increased respiratory effort.

❚  Resolution usually occurs by 2 years of age.

CASE 3� A four year old boy is

brought in after a 3 day history of a worsening barky cough, stridor, and a low grade fever.

� On the drive over, the symptoms seem to settle somewhat. However, from the “Asthma Corner” you hear:

WHAT IS YOUR DIFFERENTIAL

DIAGNOSIS?

WHAT WOULD YOU DO RIGHT AWAY/NOT DO RIGHT AWAY? Subglottic Tracheal Diseases

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QUESTION: Croup

� In what age group does croup most often occur?� What are the pathogens which cause croup?� What exactly is croup?� What is the “Westley Croup Score”?� How is croup managed?� What are the indications for admission?

Croup

❚  Most common upper respiratory obstruction in childhood.

❚  Range of age is 6 months to 6 years with the peak incidence occurring at 2 years.

❚  Usually occurs in late fall, early winter, and spring.

Pathogens❚  Parainfluenza virus type I causes most cases of

croup, up to 60% depending on the study.

❚  Parainfluenza types II, III, and IV; influenza A and B; adenovirus; respiratory syncytial virus; herpes simplex virus; measles; rhinovirus; coxsackievirus A and B; echovirus all can cause mild sporadic croup.

❚  Influenza A has been implicated in children with severe symptoms.

Definition❚  Croup is caused by

inflammation and edema of the mucosal and submucosal tissues of the subglottic space.

❚  The mucosa, bordered by the cricoid ring, swells into the airway lumen.

Clinical

History❚  Croup begins with a prodrome of a few days of

mild upper respiratory infection with coryza, nasal congestion, sore throat, and cough.

❚  A low grade fever, seldom higher than 39ºC.❚  A hoarse voice and harsh, bark-like cough

follow.❚  Respiratory stridor usually develops at night.

Physical Exam❚  Typical constellation:

❚  Barky cough❚  Hoarse voice❚  High pitched inspiratory

stridor

❚  Respiratory and heart rate are also important determinants of severity.

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ManagementMild & Moderate❚  Mist

❚  Loosens thick secretions❚  Improves symptoms within 10 to 20 minutes

❚  Racemic Epinephrine❚  Acts on the alpha receptors of the subglottic mucosa causing

vasoconstriction thereby reversing edema.❚  Onset of action is 10 minutes❚  Patients can be discharged safely after 2 to 4 hours of

treatment.❚  Glucocorticoids

❚  Dexamethasone 0.15 to 0.60mg/kg PO/IM as one single dose, lasts about 48 hours.

❚  Nebulized Budesonide also effective but expensive.

ManagementSevere Croup❚  Severe croup that is unresponsive to therapy may require intubation. ❚  Intubate the patient with an endotracheal tube that is 0.5-1 mm smaller

than predicted. ❚  A helium-oxygen (helium 60-80%) mixture may prevent intubation.

Reasons a �Child with Croup Might be Hospitalized

! Marked distress on presentation! Unusual symptoms: (hypoxia, high fever)! Dehydration!  Poor response to racemic epinephrine!  Persistence of stridor!  Persistence of tachycardia, tachypnea! Uncertain follow-up ability! Young age! Distance from hospital is far!  Complex past medical history! Anxious parents

CASE 4� A four year old girl is

brought in after a 3 day history of a worsening barky cough, stridor, and a high fever.

� When you go to the crash room you see a little girl who is pale, cyanotic, and in severe distress.

WHAT IS YOUR DIFFERENTIAL

DIAGNOSIS?

WHAT WOULD YOU DO RIGHT AWAY/NOT DO RIGHT AWAY?

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Diseases of the Trachea

❚  Congenital❚  Tracheomalacia❚  Tracheal Stenosis❚  Vascular Ring

❚  Acquired❚  Bacterial Tracheitis

Tracheomalacia❚  Definition:

A process characterized by flaccidity of the supporting tracheal cartilage, widening of the posterior membranous wall, and reduced AP airway diameter.

TracheomalaciaType I

Congenital or intrinsic tracheal abnormalities that can be associated with a tracheoesophageal fistula

Type IIExtrinsic defects or anomalies, such as a vascular ring causing undue pressure on the trachea

Type IIIAcquired tracheomalacia that occurs with prolonged intubation or chronic tracheal infections

History❚  Infants present after a few weeks of life with

expiratory stridor❚  Expiratory stridor may worsen with supine position,

crying, and respiratory infections. ❚  Feeding difficulties ❚  Hoarseness, aphonia, and breathing❚  Obtain history of an acquired etiology:

–  prolonged intubation–  tracheostomy–  chest trauma–  recurrent tracheobronchitis –  cartilage disorder (relapsing polychondritis)–  lung resection

Physical❚  Accessory muscle use ❚  Thoracic deformity may be present in cases

of chronic tracheomalacia, especially in younger patients

❚  Normal inspiration but abnormal expiratory noises on auscultation

❚  Growth failure

Diagnosis❚  Plain x-ray films are usually non-

diagnostic❚  Dynamic studies such as

fluoroscopy or ultra fast CT tend to be more useful

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Treatment❚  Supportive therapy is provided to most infants❚  Conservative management, consisting of

humidified air, chest physical therapy, slow and careful feedings, and control of infection and secretions with antibiotics.

❚  The use of continuous positive airway pressure (CPAP) in patients with respiratory distress

Bacterial TracheitisPathophysiology❚  Bacterial tracheitis is a diffuse inflammatory process of the

larynx, trachea, and bronchi with adherent or semi adherent mucopurulent membranes within the trachea.

❚  The lining of the trachea forms a loosely adherent membrane that sloughs into the lumen.

Peak AgeRange is 3 weeks to 16 years with the peak age occurring around 4 years.

Bacterial TracheitisHistorical Features:☛ Symptoms intermediate between epiglottitis and

croup.☛ Typically a viral prodrome of fever, barky cough,

and stridor with progression to higher fever, cough, inspiratory stridor, and a variable degree of respiratory distress.

☛ Patients may decompensate acutely with worsening respiratory distress due to airway obstruction from a purulent membrane that has loosened

Bacterial TracheitisPhysical Findings:☛  Inspiratory and expiratory stridor☛  Barky cough☛  Hoarseness☛  Variable degrees of respiratory distress☛  Accessory muscle use☛  Dyspnea☛  Nasal flaring☛  Cyanosis☛  Sore throat, odynophagia☛  No drooling*☛  No specific position of comfort (The patient may lie supine)*☛  Worsening or abruptly occurring stridor or respiratory distress☛  Does not respond to typical treatment for croup (steroids &

epi)

Bacterial Tracheitis☛  WBC

☛  Normal or slightly increased

☛  Blood cultures☛ Frequently negative

☛  X-rays☛ PORTABLE & ONLY IF

PATIENT IS STABLE☛ Lateral and AP views of the neck

and chest☛ Subglottic narrowing☛ Ragged tracheal edge☛ Hazy density within the tracheal

lumen☛ Coexisting pneumonia of CXR

Management

Bronchoscopy:☛ Both diagnostic and therapeutic☛ Should occur emergently☛ Allows for visualization of the upper airway to

exclude other diagnoses☛ Allows for suctioning of debris and secretions☛ Facilitates the establishment of an artificial airway

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Management

Airway:☛ Avoid agitating the child.☛ If respiratory status suddenly deteriorates, BVM

ventilation is usually effective.☛ Intubation is required over 70% of the time.☛ If intubation is required, use an endotracheal tube

0.5-1 size smaller than expected in order to minimize trauma in the inflamed subglottic area.

Management

Medication:☛  IV access for fluid resuscitation and initiation of

antibiotics☛ Antibiotics: penicillinase-resistant penicillin and a

third-generation cephalosporin (e.g. cefotaxime), or chloramphenicol and clindamycin for patients who are allergic to penicillin. Can use vancomycin in severe cases.

Credits◆ Copyright protected material used with permission of the authors and the University of Iowa's Virtual Hospital, www.vh.org.◆ Rosen’s Emergency Medicine: Concepts and Clinical Practice◆ Emergency Medicine: A Comprehensive Study Guide◆ www.emedicine.com